Partitioned data set file naming

A partitioned data set (PDS) is a group of files contained in a library. The individual files that make up a PDS are called members. You can access an entire PDS or any individual member of a PDS.

The naming requirements for a partitioned data set are:

No part of the name can start with a numeric.
No part of the name can be more than eight characters in length.
Each part of the name is separated by a period.
If single quotation marks are not used when specifying the PDS name, the MVS™ system appends the current working directory as the first part of the name.

The difference between a sequential and partitioned data set specification is that the partitioned data set user accesses the directory of members in the PDS, and the sequential data set user accesses an individual file.

The following examples show the naming conventions for partitioned data sets on an MVS host.

To access the partitioned data set KC00852.PDS.NAMES, the user, with the current working directory ‘KC00852’, enters one of the following:

'KC00852.PDS.NAMES'
PDS.NAMES

Either of these formats is acceptable to access a partitioned data set.

Note: You can use the special character asterisk (*) as a global name character (wildcard) for pattern matching when you specify a data set name, with the following restrictions:

The asterisk must be the last character, or the only character specified for a level of qualifier.
When the data set name is enclosed in quotation marks, you cannot use the asterisk as a wildcard in the high-level qualifier of the data set name. Data set names not enclosed in quotation marks will use the setting of the current directory as the high-level qualifier.
You can use the asterisk more than once in the complete data set name, but the asterisk must be the last character for each level of data set name qualifier.
If you specify a member name, you cannot use an asterisk anywhere in the data set name.
If you use an asterisk as all or part of the member name, you cannot use an asterisk anywhere else in the data set name.

To access an individual member of a PDS, the member name is entered in parentheses.

To access the member PROPER in the PDS KC00852.PDS.NAMES, the user, with the current working directory KC00852, enters one of the following:

'KC00852.PDS.NAMES(PROPER)'
PDS.NAMES(PROPER)

Either of these formats is acceptable to access an individual member of a partitioned data set.